A comparison of two methods of presenting demonstrations in a metal casting laboratory to evaluate the effectiveness of student learning

Abstract

This investigation was conducted to compare the effectiveness of video-taped, closed-circuit television with the conventional live method of presenting selected laboratory demonstrations in basic metal casting. This study was conducted in the Industrial Technology Department of Tennessee Technological University during the fall quarter of 1969. Sixty-four students, enrolled in four class sections, were randomly assigned to control and experimental groups and were presented five laboratory demonstrations by two methods. The groups received the five technical units, the control group by direct demonstration and the experimental group by video-tape. The material for each demonstration was identical, and all visual aids used in the production of the video-tapes were available for the direct presentation, when applicable. The criteria used to evaluate both methods were (1) initial learning of subject matter and procedures after each demonstration and (2) retention of the subject matter and procedures twelve weeks after the beginning of instruction. The student's knowledge of the material was measured by administering a 120-iten achievement test four times: once as a unit basis and three times as a single instrument. Students were divided into three levels (upper, middle, and lower) by the results of the pre-test scores to determine the effectiveness of one demonstration method over another. A casting report form was used to determine the number of attempts required by each student to achieve a satisfactory casting. A record of the total number of attempts was recorded for each group for each casting required. The analysis of variance and the pooled t test were used to analyze the results gathered from the unit and achievement tests..